When you are immature, selfish, and don't give a crap about your work, your co-workers, your company, or your reputation.

Normally when you skip work and don't call in to let them know where you are, are late for work meetings, yell at your boss on national TV, get fined every week for insubordination, and shoot yourself with an unlicensed firearm in a NY nightclub which damages your very career, you might say you are feeling Plaxidaisical about your job.